Such devices have a larger chamber for holding gasoline, a smaller chamber for holding oil, a separation plane between the chambers, and a thin connecting member arranged between the chambers in the separation plane and forming part of the chambers. A handle straddles the separation plane, and has a handle root that begins on the upper side of the larger chamber. Such a device is known from German Patent 21 49 569. Such cans are widely used by forest workers who operate chain saws powered by two-stroke engines. In practice, the two-stroke mixture is stored in the larger 5 liter chamber, while the smaller 2.5 liter chamber contains the chain lubricant. Clearly, this type of can can have many other uses. The disadvantages of this construction, which dates from 1971, are the following:
1. The thickness of connecting member 28 is somewhat less than double the thickness of the material used in construction, i.e. 5 mm. Such meagre dimensions do not provide the thickness required to separate both chambers. It must also be remembered that such cans, being produced by the blow-mold process, are rather less solidly constructed than injection-molded containers.
2. In order to remedy the instability of the connecting member, handle 3 was provided with roots, of which the first was affixed to the larger chamber, the second to the larger and smaller chambers and the third solely to the smaller chamber. This arrangement wastes material, since one need use only the handle that is situated over the center of gravity.
3. Blow-molding of this handle structure requires advanced techniques and relatively complicated blowing molds.
4. The above-mentioned second handle root limits the finger opening in the handle to a relatively small size, to the detriment of the user attempting to grasp the can, particularly if gloves are worn. There exists in Canada, for instance, a polar glove fashioned without individual finger pockets; such a glove could not possibly fit through a handle opening of this size.
5. The handle, also being blow-molded, features a cavity. Where no constriction point 34 made in the handle, the contents of the smaller chamber could be permitted to mix with the contents of the larger chamber, which would be inappropriate. The existence of such a constriction point would also weaken the handle, given the premise that a pipe composed of given quantity of material would exhibit the greatest strength if its load-bearing capacity were uncompromised in all directions.
6. It is not possible in this case to use the handle cavity for returning, during pouring, air to the rear of the larger chamber.
7. The rectilinear construction of the connecting member imposes at least upon upon the smaller chamber a somewhat flat rectangular shape, which has not proved to be especially resistant in impact tests.